"He will reign on David’s throne and over his kingdom, establishing it with justice and righteousness" (Isa. 9:7).
Although the kingdom of God existed in Old Testament times, everything prior to Christ’s advent was preparatory. The kingdom of Israel functioned only as a type of that which would come. The eternal king was not David, but the Messiah who would gather subjects from all nations and rule over all things. Numbers 24:17 says, “There shall come a Star out of Jacob; and a Scepter shall rise out of Israel.” 2 Samuel 7:16 describes the covenant God made with David: “Your house and your kingdom shall be established forever before you. Your throne shall be established forever.”
Christ fulfilled these promises as Immanuel, the “Wonderful Counselor, the Mighty God, the Everlasting Father, the Prince of Peace. Of the increase of His government and peace there will be no end, upon the throne of David, and over his kingdom, to order it and establish it with judgment and justice from that time forward, even forever.”
Christ’s dominion extends over the entire universe—His kingdom of power. But His kingdom of grace includes only those whom He has rescued from the kingdom of darkness. Those who believe in Him are part of the kingdom of heaven, which is so called because it is spiritual (John 18:36) and has a heavenly end. It is called the kingdom of Christ because He is the ruler of it. All who believe in Him and who have repented of their sins live in this kingdom (John 3:3–5). They are subject to the King and are expected to live in righteousness and obey the laws of the kingdom—to love God and one another (Gal. 5:19–21; 2 Cor. 8). They receive the protection and blessings of the King.
The kingdom of Christ will ultimately be consummated in the future—when all the elect are gathered and the new heaven and new earth replace this present reality. This will be the kingdom of glory. In this kingdom the tares will be separated from the wheat. All the redeemed will possess resurrected bodies and live forever, worshiping and delighting in the King of glory.
No one knows when the kingdom of Christ will be consummated, but until that time, we are to obey Him and spread the Gospel, so that all God’s people might bring glory and praise to Him.
Do you get discouraged by ungodly aspects of your government and by the unrighteousness that pervades national institutions? Do you long for justice to prevail? If so, find encouragement in the promise that Christ’s kingdom is one of righteousness and justice. Find security in your heavenly King, not in earthly governments.